This invention relates to an energy network for providing hydrogen generated at a production site, particularly by one or more water electrolysers, for use particularly, as a fuel for vehicles or energy storage. The invention further relates to the use of hydrogen as a fuel for a fuel cell wherein hydrogen is converted into electrical energy, for combustion as an auxiliary energy source and for the generation of electricity, particularly, as part of an electrical distribution system.
In planning the production capacity of a large chemical plant, for example, for methanol production or a large electricity production site, correct knowledge of expected demand of the product is critical with regard to the optimization of capital deployment and certainty of a return on investment in the large facility. Most often millions of dollars are required to finance the construction. Thus, measuring and predicting the supply and demand for the end product is highly desirable. Applying techniques to predict future demand on a real time, short, medium or long term basis, commercially, is extremely important, particularly for maximizing asset utilization, reducing inventory, and minimizing risk.
Currently, the widespread deployment of a network of hydrogen supply systems for hydrogen-fueled vehicles does not exist. At present, there is a widespread network of hydrocarbon-fueled vehicles complete with an optimized fuel supply infrastructure network based on the limits of known technology, society""s standards and consumer acceptance. Many believe to put a widespread, geographic network of hydrogen vehicles with a network of hydrogen supply encompassing production, storage, transportation and delivery would involve such a large investment and be so challenging, that the task is believed essentially impossible to do in any economic method. Although, there are numerous examples of hydrogen production from electricity close to where it can be used to fuel a vehicle, such individual sites are not interconnected so as to optimize performance and asset deployment.
There are a number of shortcomings of the current hydrocarbon-fueled vehicle distribution networks, which shortcomings include a finite resource of the hydrocarbon fuel per se and an uneven distribution of the world""s resources. In fact, much of the world""s hydrocarbon resources are focused in just a few geographical areas, such that many nations do not have a substantive supply of indigenous fuel. This has led to global and regional conflict. In addition, there is uncertainty about the impact of greenhouse gas emissions on health and climate change. Furthermore, the very use of hydrocarbon fuels, or the processing for use of hydrocarbon fuels, leads to ground level pollution of smog and ozone as well as regional environmental challenges, such as acid rain. Airborne pollutants, either directly or indirectly formed due to the combustion or processing of hydrocarbon fuels, lead to reduced crop output, potentially reduced lifespan and other health issues for all living beings.
A network of fuel supply systems which could provide as good, if not better, consumer service and reduce or eliminate fuel resource disparity, negative environmental aspects of hydrocarbon fuels and their combustion or processing which can be introduced in a manner which mitigates the investment risk, optimizes the capacity factor of all equipment in the system and encourages the use of non-carbon energy sources is highly desirable. Hydrogen fuel, produced from energy sources which are lower in carbon content than conventional coal and oil, or hydrogen fuel produced from coal and oil in which the carbon is sequestered below the surface of the earth, would be an ideal fuel for this network.
One aspect of the delivery of a product from a production site to a utilization site involves the use of storage. Storage of the product, sometimes a commodity, can efficiently allow for supply and demand to meet in a manner which optimizes the utilization of production. Two examples of this is the supply of hydrogen produced
(a) from methanol on board a vehicle and used in a car, where on board it is reformed into a hydrogen containing gas; and
(b) by electricity off-board a vehicle and used to fill a compressed gas storage tank either on the vehicle or on the ground for subsequent transfer to the vehicle.
In latter case (b), the hydrogen is produced off-board the vehicle and is stored in a compressed gas tank, or similar container. The accumulation of hydrogen disconnects the production of electricity for hydrogen production with the real-time demand for hydrogen. This load shifting effect on electricity production, enabled by storage of hydrogen, enables better and more predictable utilization of electricityxe2x80x94particularly when the hydrogen demand is of some significant percentage, say 1% to 100% with regard to the electricity being produced. This enables decisions to be made on a real time basis as to where to direct the electricity, for example, to hydrogen production by electrolysis or other uses. This is only part of the equation as it enables measurement of the supply of electricity, i.e. at times where incremental production of electricity is available or advantageous and includes many aspects of operating an electrical generator, transmission, and distribution system which creates improved asset utilization for hydrogen production in addition to meeting immediate real time electrical demand. The second half of the equation is the measurement of hydrogen demand in essentially real time. This involves planning for the production of hydrogen. When the hydrogen production is from electrolysis sources and the hydrogen is transferred to the storage tank on board the vehicle from a storage tank or directly from an electrolyser base to meet the need demanded by the market place for hydrogen, measurement on a moment by moment basis is possible of the hydrogen demand. The demand can be understood by those familiar in the art by techniques such as temperature/pressure measurements as well as electrical energy consumption. In addition, measurement of the amount of hydrogen energy on board the vehicle can enable information to be provided to the controller for hydrogen supply from electricity production and can be equated to stored energy/electrical resources. These measurements complete the equation for supply and demand with detailed measurement. This enables the following:
(a) real time predictions of the amount of electricity required in the following time periods: instantaneous and, when combined with previous data, the rate of growth of demand for electricity for hydrogen production;
(b) the deferred use of electricity for hydrogen production and the supply of electricity to a demand of a higher priority (economic or technical);
(c) the safe curtailment of electricity supply for the use of hydrogen production as sufficient storage exists in the xe2x80x98system networkxe2x80x99 of storage tanks; and
(d) the ability to develop xe2x80x98virtualxe2x80x99 storage reservoirs where by priority/cost/manner of supply of electricity can be determined based on the status of the storage reservoir.
A system which connects electricity production decision making to stored hydrogen, either on board a vehicle or on the ground to hydrogen markets enables better decision making with regard to when, where, and how much electricity to provide. This information, available on essentially an instantaneous basis through measurement, is critical to asset deployment and increase asset utilization and risk mitigation. It can also be used to better schedule electrical generators. By acting as an xe2x80x9cinterruptible loadxe2x80x9d it can provide operating reserves for the electrical utility to meet reliability requirements. By collecting this information through appropriate means a novel and inventive measurement system is created which incorporate the features incorporating one or more of a,b,c and d above.
It can, thus, be seen that the decisions concerning a chemical plant for, say, methanol production which then is used for many applications including on-board or off-board reforming of methanol can not provide instantaneous and daily information to influence production decisions.
It is thus an object of the present invention to provide an energy distribution network incorporating hydrogen which provides for effective deployment and utilization of electrical generation, transmission and distribution capacity and enhanced economic performance of such assets.
The invention in its general aspect embodies a network having:
(a) primary energy sources transmitted from their production sources to a hydrogen production site;
(b) hydrogen production and delivery equipment with or without by-product sequestration equipment, with or without on-ground hydrogen storage equipment; and
(c) collection, storage and supply controllers for the communication of data.
The term controller comprises central processing means and computing means for receiving, treating, forwarding and, optionally, storing data.
The practice of the invention involves use of algorithmic manipulations within the controller(s) to utilize and determine information data relating to, inter alia, the amount of hydrogen required from an electrolyser(s) by the user(s), the time of delivery of electrical energy to the electrolyser, duration of period the energy is to be delivered to the electrolyser(s), the energy level to be sent to the electrolyser(s), the hydrogen pressure of the user storage, real time price of electricity and price forecast, rate of energy level or the type of modulation of the energy resource(s) to the electrolyser(s); and the types of electrical energy selected from fossil fuels, hydro, nuclear, solar and wind generated.
The algorithmic manipulations within the controller(s) further determine the control stages operative in the practice of the invention, such as, inter alia, the operation of the energy resources(s), electrolytic cell(s), compressor valves, user activation units, and the like as hereafter described.
By combining the above elements together, a network that measures real-time and computed expected demand for hydrogen fuel and provides product hydrogen accordingly is realized. This network may be linked with standard projection models to predict future demand requirements by geographic location. A preferred feature of this hydrogen network is that it does not rely on the construction of large scale hydrogen production facilities of any kind. Instead, preferred hydrogen production facilities provided herein are as small as technically/commercially feasible and include scaled-down apparatus to meet the needs of a single consumer or a plurality of customers from a single commercial, retail or industrial site.
Accordingly, in its broadest aspect, the invention provides an energy distribution network for providing hydrogen fuel to a user comprising: hydrogen fuel production means; raw material supply means to said production means; hydrogen fuel user means; and information and supply control means linked to said production means, said raw material supply means and user means.
The term xe2x80x98hydrogen fuel user meansxe2x80x99 in this specification means a recipient for the hydrogen produced by the hydrogen production means. It includes, for example, but is not limited thereto: hydrogen storage facilitiesxe2x80x94which may be above or below ground, in a vehicle and other transportation units; direct and indirect hydrogen consuming conversion apparatus and equipment, such as fuel cell, electrical and thermal generating apparatus; and conduits, compressors and like transmission apparatus. The demand may also be initiated by the energy supply, which may need to xe2x80x9cdumpxe2x80x9d power and thus offer an opportunity to produce cheaper hydrogen.
The raw material(s) may include, for example, natural gas, a liquid hydrocarbon or, in the case of an electrolyser, electrical current and water.
With reference to the practice of the invention relating to natural gas, natural gas from a remote field, is put in a pipeline and transported to a retail outlet or fuel supply location for a hydrogen fuel. At or near the retail outlet or fuel supply location, the natural gas is steam/methane reformed with purification to produce hydrogen gas. The carbon dioxide by-product is vented or handled in another manner that leads to its sequestration. The hydrogen produced may be fed, for example, into a vehicle""s compressed hydrogen gas storage tank through use of compression. Alternatively, the compressor may divert the flow to a storage tank, nominally on the ground near the steam methane reformer/compressor system. The amount of hydrogen produced in a given day is determined in many ways familiar in the art and includes natural gas consumption, hydrogen production, storage pressure, rate of change, and the like. This information is electronically or otherwise transferred to the operator of the network according to the invention. This information over time constitutes demand information for hydrogen from which supply requirements can be foreseen as well as future demand predicted. As the demand for hydrogen grows, the network operator may install a larger natural gas reformer or add more storage tanks to make better use of the existing generator when demand is low. The ability to measure and store hydrogen, enables better decisions to be made than with the current liquid hydrocarbon (gasoline) infrastructure. The measuring ability enables predictions for the raw material (natural gas in this case) to be determined. If the natural gas comes from a pipeline, the supply/demand characteristics provides useful information on how to better manage the pipeline of natural gas as well as plan for purchases expansion, trunk extensions, maintenance, amortization of capital assets, and even discoveries of natural gas. The measuring ability of the system also provides key information on predictions for vehicle demand as the growth rate of hydrogen demand for vehicle use may be a significant leading indicator.
With reference to a network according to the invention based on the current popular fuels, gasoline and diesel, produced from a network of oil wells, and refineries, this fuel is shipped to a retail outlet or fuel supply location. As needed, the gasoline/diesel is reformed or partially oxidized, or other chemical steps taken to produce hydrogen. After sufficient purification, the hydrogen is either stored directly on to the vehicle or at off-vehicle storage sites for latter on-vehicle transfer. The amount of hydrogen produced in a given day is determined by those knowledgeable in the art based on gasoline/diesel consumption, hydrogen production, storage levels or pressures of gas storage, rates of change, and the like. This information is electronically or otherwise transferred to the operator of the network according to the invention. This information over time constitutes demand information for hydrogen from which supply requirements are foreseen as well as future demand predicted. As the demand for hydrogen grows, the network operator may install a larger gasoline/diesel reformer or add more storage tanks to make better use of the existing generator when demand is low. The ability to measure and store hydrogen, enables better decisions to be made with regard to deployment of assets, such as storage tanks and more hydrogen production equipment, than with the current liquid hydrocarbon (gasoline/diesel) infrastructure. The measuring ability enables predictions for the raw material to be determined. This is particularly important if the gasoline/diesel is specifically produced for low pollution or zero emission vehicles in regards to octane, additives, detergents, sulphur content, and the like and there is a unique capital structure to the assets used to produce, transport and distribute this special grade of gasoline/diesel. The measuring ability of the system according to the invention also provides key information on predictions for vehicle demand as the growth rate of hydrogen demand for vehicle use is a very significant leading indicator.
With reference to a network according to the invention based on a liquid hydrocarbon, such as methanol, methanol produced from a network of generating plants spread locally or globally, is shipped to a retail outlet or fuel supply station location. As needed, the methanol is reformed, partially oxidized, or other chemical steps taken to produce hydrogen. After sufficient purification, the hydrogen may be stored directly on to the vehicle or non-vehicle storage for later vehicle transfer. The amount of hydrogen produced in a given day could be determined as described hereinabove with reference to natural gas and gasoline.
However, a most preferred network is based on using electricity for water electrolysis. Electricity travelling in a conductor, produced from a network of generating plants spread locally or globally, is fed to a residence, home and the like, a commercial or industrial retail outlet or other fuel supply location. As needed, the electricity is used in an electrolysis process that produces hydrogen and oxygen that is of value. After sufficient purification and compression if required, the hydrogen may be stored directly on to a vehicle or fed to non-vehicle storage.
Electricity can come from many different types of primary energies, each with their own characteristics and optimal ways and means of production. Once electricity is produced, it is difficult to store effectively and must be transmitted through some form of distribution/transmission system. Such systems must respond to many different circumstances of users, multiple users more so than from a natural gas pipeline, time of use variation, load density, primary electrical input source, status of primary electrical input source, weather conditions, unique aspects of dealing with the nature of electricity, versus a gas or a liquid.
An electrolysis unit, particularly an appropriately designed water electrolysis system, has unique advantages in how it can be connected to electricity supplies and does not have to operate continuously. An electrolyser can be made to start, stop or modulate in partial load steps more readily than the typical methods to produce hydrogen from hydrocarbons. This factor is a key element in that electricity may be dynamically xe2x80x9cswitchedxe2x80x9d from hydrogen production to other electrical loads based on a priority schedule. This feature enables an electrolyser to obtain lower cost electricity than higher priority electrical loads. Further, since electrolysis is a very scalable technology from 1 less than kW to over 100,000 kW, the same system, variant only in size, has the potential to be distributed, as needed. Thus, it can provide control activation for meeting changes in electrical demand dynamically.
In the practice of the present invention in a preferred embodiment, the wires that deliver the electrical energy to the electrolyser are used to communicate useful information about the state of the electrolysis process to related devices. This eliminates the need for an additional connection or a xe2x80x9ctelemetry devicexe2x80x9d to collect necessary information in an electronic fashion.
Thus, a hydrogen fuel network incorporating electricity and electrolysis offers useful opportunities with intermittent renewable energy sources, e.g. photovoltaics and wind turbines, even though these may be located hundreds of miles away from a network of electrolysis-based hydrogen generators. The hydrogen generators can be sequenced to produce hydrogen at a rate proportional to the availability of renewable energy sources. In addition, by measuring price signals, the electrolysers can be reduced or shut down if the market price for electricity from a particular generation source is beyond a tolerance level for fuel supply. The electrolysis system can also be readily shut down in the case of emergency within the electrical system. In view of the speed of data communications, control actions which can be taken in less than one second can be uses to dynamically control the grid as well as replace spinning reserves to meet reliability requirements.
Only a natural gas distribution system is close to an electricity system in the concept of a continuous trickle supply of the energy source to the hydrogen generator. When gasoline or methanol arrives at a hydrogen production and fuel supply site, it is generally by large shipment and the gasoline or methanol would be stored in a tank of some 50,000 gallons size. The trickle charge is a critical feature of the hydrogen fuel network and is clearly preferred. The distributed storage of hydrogenxe2x80x94either on the vehicle which itself may be trickle charged or for an on ground storage tank which can be trickle charged, accumulate sufficient hydrogen and then deliver that hydrogen to a car at a power rate measured in GW. The ability to take a kW trickle charge and convert it to a GW rapid fuel power delivery system through effective storage is a key element in building an effective fuel supply service as a product of the network.
The ability to measure hydrogen supply and demand as well as estimate the total hydrogen stored in the network, including ground storage or storage on board vehicles, provides a most useful benefit of the network of the invention. The integrated whole of the network is analogous to a giant fuel gauge and, thus, predictions of the amount of electricity required to fuel the system and the rate of fueling required can be made. This provides electricity power generators/marketers information from which they can help better predict supply and demand real time. Uniquely, the location as to where the fuel is most needed can also be determined on a near continuous basis.
In addition, distributed hydrogen storage, a consequence of the network according to the invention, is similar to distributed electricity storage or, if integrated together, a large hydroelectric storage reservoir. The hydrogen storage reservoir, may optionally, be converted back to electricity for the grid using an appropriate conversion device such as a fuel cell. Most objectives of energy management obtained with hydroelectric water reservoirs may be practiced with hydrogen reservoirs. Given the distributed network of hydrogen reservoirs, the priority of practicing a particular energy management technique can be performed. This prioritization capability is unique to the network of the invention.
As a network incorporating distributed electrolysis-based hydrogen supply systems with distributed reservoirs is developed, the planning for the addition of new electricity generation systems can be made based on information from the network. The uniqueness of knowing the supply, demand and energy storage aspects of the network provides information about the optimal specification of new electrical generating systems. The creation of large scale energy storage capability encourages selection of electrical generators previously challenged by the lack of energy storage. Such generators including wind turbines and photovoltaic panels may be encouraged. This should optimize the ability to implement these types of generators which may be mandated by governments as necessary to combat perceived environmental challenges.
The hydrogen network in the further preferred embodiments enables money payments to be made for services provided in real time as for preferred forms of energy sources based on environmental impact.
Thus, the network of energy sources of use in the practice of the invention produces hydrogen through various techniques, such as steam methane reforming, partial oxidation or water electrolysis, at, or very near, the intended user site so that no further processing beyond appropriate purification and pressurization for the specific storage tank/energy application. In the case where the hydrogen energy comes directly or indirectly from a carbon source which is deemed by society to be too high in carbon content (CO2 production) or where other pollutants may exist, these are captured at source and sequestered to the extent society deems necessary. In addition, a method to measure, or reasonably estimate the flow of hydrogen into storage (compressed gas, liquid H2, hydrides, etc.) in or on the ground or an appropriate storage system on board a vehicle is helpful to obtain information which can lead to decisions as to when, where and how to produce fuel as well as when to deploy more assets in the process of producing fuel or on board a vehicle measurements.
Thus, the invention in one most preferred embodiment provides a hydrogen fuel vehicle supply infrastructure which is based on a connected network of hydrogen fuel electrolysers. The electrolysers and control associated means on the network communicate current electrical demand and receive from the electrical system operator/scheduler the amount of hydrogen fuel needed to be produced and related data such as the time period for refueling. For example, based on the pressure of the storage volume and the rate at which the pressure rises, the storage volume needed to be filled can be calculated. The time period for fueling may also be communicated to the fuel scheduler, for example, by the setting of a timer on the electrolyser appliance and/or the mode of operation, e.g. to be a quick or slow fuel fill. The electrical system operator/fuel delivery scheduler may preferably aggregate the electrical loads on the network and optimize the operation of the electrical system by controlling the individual operation of fuel appliance, using xe2x80x98scheduledxe2x80x99 hydrogen production as a form of virtual storage to manage and even control the electrical system; and employ power load leveling to improve transmission and generating utilization, and dynamic control for controlling line frequency.
It is, therefore, a most preferred object of the present invention to provide a real time hydrogen based network of multiple hydrogen fuel transfer sites based on either primary energy sources which may or may not be connected in real time.
There is preferably a plurality of such electrolysers on the energy network according to the invention and/or a plurality of users per electrolysers on the system.
In a preferred aspect, the network of the invention comprises one or more hydrogen replenishment systems for providing hydrogen to a user, said systems comprising
(i) an electrolytic cell for providing source hydrogen;
(ii) a compression means for providing outlet hydrogen at an outlet pressure;
(iii) means for feeding said source hydrogen to said compressor means;
(iv) means for feeding said outlet hydrogen to said user;
(v) control means for activating said cell to provide said hydrogen source when said outlet pressure fall to a selected minimum value; and
(vi) user activation means for operably activating said control means.
The aforesaid replenishment system may comprise wherein said electrolytic cell comprises said compression means whereby said outlet hydrogen comprises source hydrogen and said step (iii) is constituted by said cell and, optionally, wherein a hydrogen fuel appliance apparatus comprising the system as aforesaid wherein said means (iv) comprises vehicle attachment means attachable to a vehicle to provide said outlet hydrogen as fuel to said vehicle.
The invention in a further broad aspect provides a network as hereinbefore defined further comprising energy generation means linked to the user means to provide energy from the stored hydrogen to the user.
The energy generation means is preferably one for generating electricity from the stored hydrogen for use in relatively small local area electricity distribution networks, e.g. residences, apartment complexes, commercial and industrial buildings or sites, or for feeding the auxiliary generated electrical power back into a wide area electricity distribution network, like national, state or provincial grids, on demand, when conventional electricity power supply is provided at peak periods. The energy generation means using hydrogen as a source of fuel can utilize direct energy conversion devices such as fuel cells to convert hydrogen directly to electricity, and can utilize indirect energy conversion devices such as generators/steam turbine to produce electricity, and can utilize the hydrogen directly as a combustible fuel as in residential heating/cooking etc.
Accordingly, in a further aspect, the invention provides an energy distribution network for providing hydrogen fuel to a user comprising
(a) energy resource means;
(b) hydrogen production means to receive said energy from said energy resource means;
(c) hydrogen fuel user means to receive hydrogen from said hydrogen production means; and
(d) data collection, storage, control and supply means linked to said energy resource means, said hydrogen production means and said hydrogen fuel user means to determine, control and supply hydrogen from said hydrogen production means;
wherein said hydrogen fuel user means comprises a plurality of geographic zones located within or associated with at least one building structure selected from the group consisting of an office, plant, factory, warehouse, shopping mall, apartment, and linked, semi-linked or detached residential dwelling wherein at least one of said geographic zones has zone data control and supply means linked to said data collection, storage, control and supply means as hereinbefore defined to said geographic zones.
The invention further provides a network as hereinbefore defined wherein each of at least two of said geographic zones has zone data control and supply means, and a building data control and supply means linked to (i) said data collection, storage, control and supply means, and (ii) each of at least two of said geographic zone data control and supply means in an interconnected network, to determine, control and supply hydrogen from said hydrogen production means to said geographic zones.